Semiconductor substrates can be processed in batches in vertical furnaces. An example of such processing is the deposition of films of various materials on the substrates. For a variety of reasons, including uniformity of electrical and physical properties, high purity and uniformity is typically desired for the deposited films. Deposition results, however, can be adversely affected by the presence of particulate matter in the furnace. In some cases, the particles can come to rest on or be incorporated into the films, thus degrading the purity and uniformity of the deposited films.
Accordingly, to consistently achieve high quality process results, a need exists for processing methods and systems that can consistently achieve low particle levels.